Passive Optical Networking (PON) enables the shared use of fiber for services such as data, voice and video over most of the distance between a central office and service subscriber sites. PON is significantly less expensive to deploy and operate due to the compact size and passive nature of much of the equipment comprised by the PON facilities. For example, a passive optical splitter that fans the fiber out to service subscribers in a PON is relatively small, uses no electronics and requires no power source.
Current and emerging PON solutions offer cost-effective, end-to-end solutions that are capable of delivering a combination of high-demand services. Specific examples of such current and emerging PON solutions include Broadband PON (BPON), Ethernet PON (EPON) and Gigabit PON (GPON). Examples of services that can be provided via such PON solutions include various types of telephony services, data transmission services and video services. Signals for such services are transported optically from the central office (CO) or headend (HE) to an optical-network termination unit (ONTU) at a service subscriber's site. The ONT is configured for providing optical network termination functionality and, in some implementations, to also provide conventional network interface device functionality.
A bandwidth allocation mechanism allows for bandwidth allocation for active ONTUs to be adjusted dependent upon factors such as real-time bandwidth requirements, QOS commitments and the like. Various conventional bandwidth allocation mechanisms, such as those solutions utilizing idle-cell detection and buffer status reporting, are known. Such conventional dynamic bandwidth allocation solutions are typically implemented via hardware, software, firmware or a combination thereof.
One limitation of conventional bandwidth allocation approaches that they rely on a fixed size RAM (Random Access Memory) block for storing the grants. In such conventional bandwidth allocation approaches, the block increments the index and points to the next entry in the table each time a grant is sent to an ONTU. This operation continues until the index pointer is at the end and it wraps around to the beginning. A drawback of this approach to bandwidth allocation is that it is limited in its ability to achieve a constant grant rate for a particular ONTU. The reason for this limitation is that processor functionality of such conventional bandwidth allocation approaches is limited in their ability to space the grants out a balanced and constant manner. Another drawback is that multiple grant generators are required for generating grants for the plurality of ONTUs comprised by a PON.
Therefore, methods and systems configured for facilitating bandwidth allocation functionality in a manner that overcomes drawbacks and limitations associated with conventional approaches for facilitating bandwidth allocation functionality would be novel, useful and advantageous.